Mixing apparatus

ABSTRACT

The invention disclosed herein describes a mixing apparatus for mixing a second liquid with a first liquid. The mixing apparatus includes a housing having a bushing located therein, the bushing functioning as an eductor means for entraining the second liquid into the first liquid. A pair of axial grooves are defined on the outer surface of the bushing to permit a portion of the first liquid to be bypassed past the eductor means.

United States Patent [72] Inventor Fredolph M. Forsman Altadena, Calif. [21] Appl. No. 811,311 [22] Filed Mar. 28, 1969 [45] Patented Sept. 28, 1971 [73] Assignee The Leisure Group, Inc.

Los Angeles, Calif.

[54] MIXING APPARATUS 5 Claims, 4 Drawing Figs.

[52] US. Cl 239/318, 239/317, 239/422, 239/426, 239/434 [51] Int. Cl 1305b 7/30 [50] Field oi Search 239/434, 426, 318, 422, 427, 310. 317, 347, 370, 364, 361, 354, 425.5

[56] References Cited UNITED STATES PATENTS 2,850,323 9/1958 Veres 239/354 2,719,704 10/1955 Anderson etal 239/318 X 2,800,313 7/1957 Targosh et a1. 239/318 X 3,088,679 5/1963 Ford 239/434 X 3,446,438 5/1969 Watson 239/318 X Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-Thomas C. Culp Jr. Attorney-Jackson & Jones ABSTRACT: The invention disclosed herein describes a mixing apparatus for mixing a second liquid with a first liquid. The mixing apparatus includes a housing having a bushing located therein, the bushing functioning as an eductor means for en training the second liquid into the first liquid. A pair of axial grooves are defined on the outer surface of the bushing to perrnit a portion of the first liquid to be bypassed past the eductor means.

MIXING Arm:

1. Field of the Invention The present invention relates generally to mixing apparatus, and more particularly to apparatus for mixing a second liquid with a first liquid to provide a discharge stream having a desired ratio of first and second liquids.

2. Description of the Prior Art Heretofore, various types of apparatus for mixing a first liquid with a second liquid have been widely used for applying liquid chemicals, such as fertilizers, insecticides, toxicants and fungicides to plants, trees, shrubs, lawns and agricultural crops. A common apparatus for such purposes is a sprayer adapted to communicate with the first and second liquids having educting means located therebetween to produce a suctional effect on the second liquid to educt it into the main stream of the first liquid to mix therewith, thereafter expelling the mixture through a discharge nozzle.

These sprayers, usually adapted to be connected to a garden hose, function to educt a chemical solution into a stream of water under pressure from a garden hose connected to a city water system. The sprayers maintain the ratio of educted chemical to water constant over a wide range of water pressure. This action of maintaining a constant ratio of educted chemical to water over varying water pressures is defined as proportioning.

Proportioning is extremely important when applying chemicals, such as insecticides, to plants where the water pressure is subject to change, such as with city water systems, since chemicals for garden and industrial use must be applied at a specific solution strength of a particular ratio of chemical to water to obtain the desired control of the insects or plant diseases and prevent damage to the treated plants.

Sprayers having a single eductor and mixing chamber means are capable of producing constant ratios ranging form 23:1, i.e. 24 parts water to one part chemical; up to a 60:1 ratio, but structural limitations restrict these sprayers from producing higher ratios of water to chemical. However, because of the strength of many of the chemical solutions, it is necessary for mixtures using these chemicals to have a higher ratio for proper utilization.

A possible solution to this problem is premixing the chemical solution with water before applying it by the sprayer. However, this is a tedious procedure with the possibility of improperly diluting the premixed solution with incorrect proportions.

As a result, another common type of sprayer is one having similar educting means, and means for bypassing a portion of the first liquid past the mixing chamber to later reunite with the mixed solution to be expelled from the discharge nozzle. In this manner, only a portion of the water travels through the educting means to educt the chemical solution into the mixture, which as before, is of a constant ratio ranging from 24:1 to 60:]. This mixture is then united with the bypass water for discharge, to provide a ratio of 1 :1, for example.

A disadvantage with this type of device is that the bypass means are located within the main housing shell, which is usually a metal casting. Such a casting, incorporating these bypass means, is difficult to produce and costly to manufacture. Manufacturing these devices out of plastic is also difficult because of the close tolerances required.

Another disadvantage with these prior art bypass sprayers is that the second mixing chamber where the bypass water mixes with the mixed solution forms a second venturi or inductor means whereby the bypass water creates a suction on the mixed solution to educt a still larger proportion of chemical solution into the final mixture. As a result, the main reason for which the bypass is created has been defeated.

SUMMARY OF THE INVENTION This invention obviates the above-mentioned shortcomings by providing a mixing apparatus for mixing a second liquid with a first liquid comprising a sprayer having an inlet and an outlet with a cylindrical chamber being located therebetween. The inlet of the sprayer is connected to a source of the first liquid. An eductor formed by a bushing is disposed within the cylindrical chamber with an inlet passage, aspiration chamber and difiusion passage being formed therein. At least one axial groove is formed on the outer surface of the bushing to provide a bypass conduit for bypassing a portion of the first liquid past the aspiration chamber. A choke cartridge having a discharge chamber formed therein defining the sprayer outlet is disposed within the cylindrical chamber with a space between the bushing and the choke cartridge defining a mix ing chamber, the mixing chamber being connected to the bypass conduit and the diffusion passage for permitting the mixture to be discharged through the discharge passage.

An advantage of the above device is that the bypass conduits are formed in the bushing instead of within the main sprayer housing. As a result the bushing and the main sprayer housing are easier to fabricate and more economical to produce than prior mixing apparatus.

Another advantage of the above mixing apparatus is that the mixing chamber is constructed in such a manner that the bypass liquid does not create a suction on the educted mixture to educt a still larger portion of the second liquid into the final mixture.

A primary object of the invention therefore is to provide a mixing apparatus that efficiently mixes a second liquid with a first liquid and discharges the mixture into a stream having a desired ratio of the first and second liquids.

Another object of the invention is to provide a mixing apparatus of the type disclosed that is easy to fabricate and inexpensive to manufacture.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side plan view of the mixing apparatus in accordance with the present invention;

FIG. 2 is an enlarged view of the mixing apparatus partially broken away and partially in section to show the interior structure of the device;

FIG. 3 is a perspective view of the interior bushing which houses the eductor means; and

FIG. 4 is a top sectional view of the mixing apparatus taken along lines 4--4l of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, and more particularly to FIG. 1, there is illustrated a mixing apparatus or a sprayer, generally indicated by arrow 10, having two connections 11 and 112. The connection 11 is adapted to be connected to a garden hose or other types of conduits (not shown), which, in turn is connected to a source of first liquid, such as water. A second connection 12 is adapted to be attached to a bottle 13 which contains a second liquid such as a chemical solution. Located within the interior of the sprayer 10 is an eductor means which functions to educt the chemical solution into the stream of water with the mixture being discharged through the outlet or the discharge noule. The eductor means will be described in greater detail with reference to FIGS. 2-4.

Referring now to FIG. 2, where the interior of the sprayer is more clearly shown, the connector I1 is of a cylindrical construction with the interior surface 15 being formed with thread means 16 for connection to a garden hose, or the like. Located on the interior end of the connection 11 is a screen 17 which is adapted to cooperate with an annular diaphragm to function as an antisiphon valve means. The center of the screen 17 is apertured to mate with an orifice 19 which forms the inlet of the sprayer 10. The annular diaphragm (not shown) is located adjacent the screen 17 on the upstream side thereof and is also apertured to permit the flow of water therethrough to the inlet orifice 19. The other side of the screen 17 is vented to the atmosphere through an opening 18 formed in the housing of the sprayer 10. During normal flow the diaphragm rests against the screen 17 to prevent any water from flowing through the opening 18. However, in case of any drop in back pressure, due to a break in the supply line or the like, atmospheric air would be drawn in through the opening 18 thereby preventing the chemical solution from the bottle 13 from being siphoned back into the supply line.

The inlet orifice 19 is tapered outwardly to register with a cylindrical chamber 20 which is formed within the housing of the sprayer 10. The connection 12 is also of a cylindrical construction with its interior surface 21 being formed with thread means 22 for attachment to the bottle 13. A nipple 23 extends downwardly into the interior of the connection 12, the nipple 23 having an orifice 24 formed therein which extends through the nipple 23 to the interior of the cylindrical chamber 20. A long conduit or tube is usually connected to the nipple 23 to extend to the bottom of the bottle 13 to ensure that substantially the entire amount of chemical solution contained in the bottle is withdrawn therefrom before it is necessary to refill the bottle. The upper portion of the sprayer housing 10 forms a cylindrical projection 25 having an orifice 26 formed therein which also extends from the atmosphere to the interior of the cylindrical chamber 20. Located within the cylindrical chamber 20 is a cylindrical bushing 27 which is preferably press fitted therein. The bushing 27 functions as the eductor means for educting the chemical solution within the bottle 13 into the main stream of water flowing therethrough. The bushing 27 includes a cylindrical bore 28 formed therein for receiving a second cylindrical bushing 29 which is preferably press fitted therein. An inlet passageway is formed within the bushing 29 and is defined by a pair of cylindrical bores 30 and 31 of decreasing diameters. The interior end of the bore 31 registers with an aspiration chamber 32 which also communicates with the orifices 24 and 26 by means of diametrically opposed passageways 33 and 34 respectively. A diffusion passageway is defined within the bushing 27 and is formed by a pair of cylindrical bores 35 and 36 of decreasing diameters. Finally, a choke cartridge 40 is located within the cylindrical chamber 20 and is also preferably press fitted therein. A discharge passageway 41 is defined within the choke cartridge 40 and is formed by a tapered bore 42 registering with a cylindrical bore 43, which in turn registers with an outwardly tapered bore 44, thereby forming the discharge nozzle of the sprayer 10. The space within the cylindrical chamber 20 that is located between the bushings 27 and the choke cartridge 40 is defined as a mixing chamber 45 which will be described in greater detail hereinafter.

Referring now to FIG. 3 the cylindrical bushing 27 also includes a pair of axial grooves 46 and 47 formed diametrically on the outer surface thereof. As shown in FIG. 4 the groves 46 and 47 of the bushing 27 cooperate with the interior surface of the cylindrical chamber 20 to form a pair of passageways which communicate with the inlet orifice 19 and the mixing chamber 45. These axial passageways function to bypass a portion of the water entering the inlet 19 past the eductor means formed within the bushing 27, directly to the mixing chamber 45.

In operation, with reference to FIGS. 2 and 4, water which is discharged from the garden hose at a high pressure flows through the inlet orifice and through the eductor inlet 30 and 31. Water also flows through the bypass conduits 46 and 47 due to the restriction imposed by the inlet bore 30. The water flowing through the eductor inlet 31 passes through the aspiration chamber 32 creating a partial vacuum therein. With the air orifice 26 being open, atmospheric air would be drawn through the orifice 26 and into the aspiration chamber 32 to be discharged with the stream of water through the diffusion passage 35 and 36. With the air orifice 26 being held closed, usually with the finger of the person holding the sprayer, the partial vacuum created in the aspiration chamber 32 lifts the chemical solution from the bottle 13 into the aspiration chamber 32 where it is entrained in the water system. The combined water and chemical mixture leaving the aspiration chamber 32 is confined or sealed in the diffusion passage 35 and 36 and is then discharged into the mixing chamber 45. The water passing through the bypass conduits 46 and 47 then mixes with the chemically entrained water in the mixing chamber 45, with the final mixture being discharged through the discharge orifice 41 of the choke cartridge 40. The axial grooves 46 and 47 and the inlet orifice 19 can be dimensioned to provide any specific total output requirement. The preferred embodiment discharges 1.4 gallons per minute at 40 pounds per square inch of water pressure. As can be seen the choke cartridge 40 impedes the flow of the mixture to properly mix the liquids without creating an added suction on the diffusion passageway 37 which would, in turn, generate a larger partial vacuum in the aspiration chamber 32 to educt a larger amount of chemical solution into the mixture. As a result, the mixture being discharged from the eductor means at an initial ratio of around 24:1 is then further diluted by the bypass water to raise the ratio of water to chemical to around :1 without the initial ratio being lowered. It should be noted that the housing of the sprayer 10 is usually made of a die-cast zinc while the bushing 27 is usually made of brass. As a result, incorporating the bypass means onto the bushing 27 can be done more easily and less expensively than incorporating it into the design of the zinc casting thereby enabling the entire sprayer to be fabricated more easily and manufactured at a lower cost.

What is claimed is:

l. A mixing apparatus for mixing a second liquid with a first liquid comprising:

a sprayer having an inlet and an outlet with a cylindrical chamber being located therebetween, the inlet of the sprayer being connected to a source of the first liquid;

an eductor having a housing disposed within the sprayer chamber and including an inlet passage being connected to the sprayer inlet, an aspiration chamber, and a diffusion passage connected in series;

first conduit means for connecting the aspiration chamber to the second liquid;

at lease one axial groove formed on the outer surface of said eductor housing and being connected to said sprayer inlet for bypassing a portion of the first liquid past the aspiration chamber; and

mixing chamber means located between the eductor and the sprayer outlet for connecting the bypass conduit means and the diffusion passage with the sprayer outlet, each of said axial grooves being of a constant cross section over its entire length to create a laminar flow therethrough and to prevent creating any additional suction on the eductor.

2. The combination as defined in claim 1 wherein the eductor is formed by a bushing disposed within the cylindrical sprayer chamber with the inlet passage, aspiration chamber, and diffusion passage being formed therein.

3. The combination as defined in claim 2 wherein the axial grooves are defined by a pair of axial grooves formed diametrically on the outer surface of the eductor.

4. The combination as defined in claim 2 wherein the eductor is formed by an outer bushing, having the inlet passage and an enlarged cylindrical passage adjacently formed therein, and an inner bushing having the diffusion passage formed therein being located within the cylindrical passage, with the space between the inlet passage and the inner bushing defining the aspiration chamber.

5. The combination as defined in claim 2 wherein a choke cartridge having a discharge passage formed therein defining the sprayer outlet, the choke cartridge being disposed within the sprayer chamber with the space between the eductor and the choke cartridge defining the mixing chamber. 

1. A mixing apparatus for mixing a second liquid with a first liquid comprising: a sprayer having an inlet and an outlet with a cylindrical chamber being located therebetween, the inlet of the sprayer being connected to a source of the first liquid; an eductor having a housing disposed within the sprayer chamber and including an inlet passage being connected to the sprayer inlet, an aspiration chamber, and a diffusion passage connected in series; first conduit means for connecting the aspiration chamber to the second liquid; at lease one axial groove formed on the outer surface of said eductor housing and being connected to said sprayer inlet for bypassing a portion of the first liquid past the aspiraTion chamber; and mixing chamber means located between the eductor and the sprayer outlet for connecting the bypass conduit means and the diffusion passage with the sprayer outlet, each of said axial grooves being of a constant cross section over its entire length to create a laminar flow therethrough and to prevent creating any additional suction on the eductor.
 2. The combination as defined in claim 1 wherein the eductor is formed by a bushing disposed within the cylindrical sprayer chamber with the inlet passage, aspiration chamber, and diffusion passage being formed therein.
 3. The combination as defined in claim 2 wherein the axial grooves are defined by a pair of axial grooves formed diametrically on the outer surface of the eductor.
 4. The combination as defined in claim 2 wherein the eductor is formed by an outer bushing, having the inlet passage and an enlarged cylindrical passage adjacently formed therein, and an inner bushing having the diffusion passage formed therein being located within the cylindrical passage, with the space between the inlet passage and the inner bushing defining the aspiration chamber.
 5. The combination as defined in claim 2 wherein a choke cartridge having a discharge passage formed therein defining the sprayer outlet, the choke cartridge being disposed within the sprayer chamber with the space between the eductor and the choke cartridge defining the mixing chamber. 